A305846
Inverse Weigh transform of the Bell numbers (A000110).
Original entry on oeis.org
1, 2, 3, 11, 34, 138, 610, 2976, 15612, 87905, 526274, 3334988, 22270254, 156173299, 1146640394, 8791427525, 70227355786, 583283756678, 5027823752930, 44903579714037, 414877600876638, 3959945233249877, 38996757506464858, 395749369601741015, 4134132167178705732
Offset: 1
-
g:= proc(n) option remember; `if`(n=0, 1,
add(binomial(n-1, j-1)*g(n-j), j=1..n))
end:
b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,
add(binomial(a(i), j)*b(n-i*j, i-1), j=0..n/i)))
end:
a:= proc(n) option remember; g(n)-b(n, n-1) end:
seq(a(n), n=1..30);
-
g[n_] := g[n] = If[n == 0, 1,
Sum[Binomial[n-1, j-1]*g[n-j], {j, 1, n}]];
b[n_, i_] := b[n, i] = If[n == 0, 1, If[i < 1, 0,
Sum[Binomial[a[i], j]*b[n - i*j, i - 1], {j, 0, n/i}]]];
a[n_] := a[n] = g[n] - b[n, n - 1];
Table[a[n], {n, 1, 30}] (* Jean-François Alcover, Mar 10 2022, after Alois P. Heinz *)
A290351
Euler transform of the Bell numbers (A000110).
Original entry on oeis.org
1, 1, 3, 8, 26, 88, 340, 1411, 6417, 31474, 166242, 939646, 5659613, 36158227, 244049562, 1733702757, 12919475840, 100690425442, 818554392962, 6924577964036, 60828588178031, 553821749290234, 5217264062756556, 50776256646839085, 509823607380230570
Offset: 0
-
b:= proc(n) option remember; `if`(n=0, 1, add(
b(n-j)*binomial(n-1, j-1), j=1..n))
end:
a:= proc(n) option remember; `if`(n=0, 1, add(add(d*
b(d), d=numtheory[divisors](j))*a(n-j), j=1..n)/n)
end:
seq(a(n), n=0..30);
-
b[n_]:=b[n]=If[n==0, 1, Sum[b[n - j] Binomial[n - 1, j - 1], {j, n}]]; a[n_]:=a[n]=If[n==0, 1, Sum[Sum[d*b[d], {d, Divisors[j]}] a[n - j], {j, n}]/n]; Table[a[n], {n, 0, 50}] (* Indranil Ghosh, Jul 28 2017, after Maple code *)
A305852
Weigh transform of the Fubini numbers (ordered Bell numbers, A000670).
Original entry on oeis.org
1, 1, 3, 16, 91, 658, 5567, 54917, 620081, 7905592, 112382245, 1762646331, 30231516786, 562750751610, 11297034281595, 243241826522376, 5591075279423398, 136633359995403580, 3537193288612096901, 96697587673174195740, 2783492094736121087958
Offset: 0
-
g:= proc(n) option remember; `if`(n=0, 1,
add(g(n-j)*binomial(n, j), j=1..n))
end:
b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,
add(binomial(g(i), j)*b(n-i*j, i-1), j=0..n/i)))
end:
a:= n-> b(n$2):
seq(a(n), n=0..30);
-
g[n_] := g[n] = If[n == 0, 1,
Sum[g[n - j] Binomial[n, j], {j, 1, n}]];
b[n_, i_] := b[n, i] = If[n == 0, 1, If[i<1, 0,
Sum[Binomial[g[i], j] b[n - i j, i - 1], {j, 0, n/i}]]];
a[n_] := b[n, n];
a /@ Range[0, 30] (* Jean-François Alcover, Dec 21 2020, after Alois P. Heinz *)
Showing 1-3 of 3 results.